Technology for separating low carbon olefin gases

Abstract

The invention discloses a technology for separating low carbon olefin gases, for solving the problems that hydrogen, methane, ethane and propane and other products with high purity can not be acquired and dimethyl ether and oxygen and carbon monoxide in impurities are not removed efficiently, etc. in the prior art. The technology is characterized in that a step of removing carbon monoxide and oxygen is added, methanol-to-olefin gas streams processed by removing carbon monoxide and oxygen enter into a deethanizing column, deethanizing column overhead streams successively pass through an ethene hydrogenation reactor, six separation pots, a low pressure demethanizing column and an ethene rectification column, etc. to separate to obtain ethene and ethane products, and deethanizing column bottom streams successively pass through a propyne hydrogenation reactor, a methane stripper and a propylene rectification column, etc. to separate to obtain propylene and propane products. According to the invention, polymer grade ethene and propylene products can be obtained, and hydrogen, methane, ethane and propane products, etc. with high purity can be obtained.

Description

Technical field: [0001] The invention belongs to the field of petrochemical industry, and relates to a separation process for preparing low-carbon olefin gas by converting methanol. In particular, the present invention relates to a mixture of materials comprising one or more of hydrogen, oxygen, nitrogen, carbon monoxide, carbon dioxide, methane, ethane, ethylene, acetylene, propane, propylene, cyclopropane, propyne and propadiene Process for recovering ethylene and propylene. Background technique: [0002] Olefins, especially light olefins (light olefins) such as ethylene and propylene, are required as raw materials for the production of higher olefins, polyethylene and polypropylene. The tube furnace cracking unit that uses naphtha as raw material to produce ethylene and propylene through steam cracking is currently the most important industrial production unit of ethylene and propylene. The cracked gas produced by cracking hydrocarbons is a mixture containing hydrogen, ...

AI Technical Summary

Problems solved by technology

[0021] The present invention is aimed at the disadvantages of the method disclosed in CN1833017A that products such as hydrogen, methane, ethane and propane with higher purity cannot be obtained and there is no method for effectively removing oxygen and carbon monoxide in dimethyl ether and flue gas impurities. Transformation of components and composition characteristics of light olefin gases, and a new highly effective separation process for separation of polymer grade ethylene and propylene from light olefin gases

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